1. Field of the invention
This invention relates to means for protection of vehicle windscreens, particularly during transit.
2. Prior Art
It is known, for example from EP-A-519278 (Nitto Denko) to cover the bodywork and attachments such as fenders of vehicles with adhesive film or cloth sheets to protect against damage during transport or shipping of the vehicle.
It has been found that in practice, when transporting vehicles in long ocean voyages, it is inevitable that water will find its way into the hold, and drip onto the windscreen of a vehicle. Such water will contain iron oxide due to contact with rusted surfaces within the ship and this oxide can permanently stain and damage a windscreen, particularly when a horizontal trap associated with the windscreen, such as a lower edge seal, catches the dripping water and holds it for a long time to leave behind an iron oxide residue.
Currently available protractive films or cloths are not suitable for use, since it is impracticable to apply them onto the windscreens after the vehicles have been loaded onto the ship. it is the usual procedure to apply all protective films or sheets just before leaving the factory. Since the vehicles have to be driven onto and from the ship, a typical protective film or cloth is unsuitable for use to cover the windscreen since it obscures the driver's vision.
It is a further requirement that any cover applied to the windscreen should be sufficiently abrasion resistant to withstand wiper action, in case the car is unloaded or loaded in bad weather. Ruching or peeling of the cover by the windscreen wipers will damage or remove the cover and compromise its effectiveness.
U.S. Pat. No. 5,002,326 proposes a windscreen cover of a multiplicity of polycarbonate film sheets non-permanently bonded by pressure sensitive adhesive. 12 to 16 sheets are suggested. As each exposed film is worn and degraded by exposure it is removed to expose the next film below. The initially rather thick layer is not suitable for use as a temporary cover for vehicles in transit and also the material chosen is likely to degrade due to UV exposure.
Any adhesive used must be strong enough to stick the cover to the windscreen during use of the wipers, yet be sufficiently easily releasable to remove the cover without leaving an adhesive residue on the glass.